Improvement in ventilator chimney-caps



P. MIHANL VENTILA'IOR CHIMNEY-CAPS.

No. 194,781; Patented Sept. 4,1877.

Fig.1. 1 9.2.

NIPQTERS, PHOTOLLITHOGRAPHERJ WA'SNINGTON, D Q

UNITED. STATES PATENT OFFICE.

PATRICK MIHAN, OF CAMBRIDGEPORT, MASSACHUSETTS.

IMPROVEMENT IN VENTILATOR CHIMNEV-CAPS.

Specification forming part of Letters Patent No. 194,781, dated September 4, 1877; application filed January 1'2, 1877.

its construction and eflicient in operation.

In such drawings, A denotes a tube, which may be flanged or slightly bell-mouthed at its upper end, as shown at a. Extending around the tube and arranged concentrically with it, and at a suitable distance from its upper end, is an inverted conic frustum or deflector, B, from whose superior surface or larger base a series of standards, C, project upward, and

have fixed to them at their upper ends a bonnet or dome,'D, into which and at its base the tube A projects a short distance, as shown. This dome is bell-shaped, and has at its base a diameter equal, or about equal, to that of the larger base of the deflector B, all being as represented.

When the chimney-cap so made surmounts the top of a chimney, a flue thereof should open directly into the tube A at its lower end.

The smoke, passing from the chimney-flue into the tube A, will flow therefrom into the dome, and from thence it will be discharged into the atmosphere through the opening'between such dome and the base of the deflector.

Any upward, downward, or horizontal current of air, on impinging against the ventilator or cap, will promote the escape of the smoke therefrom, and induce or increase a draft up the chimney or flue.

Instead of making the deflector B a conic frustum, asset forth, it may be a simple disk, like the base of such frustum, in which case it will operate to advantage, though not so well as it will when formed as a frustum.

The base of the frustum, instead of being a plane or disk, may be a very low frustum, inclined so as to shed water.

I claim- In the described improved chimney cap or ventilator, the stationary dome D and the inverted and closedconical deflector B, arranged, as represented, in combination with the pipe A, concentric with the deflector and dome, and extended above the former and upward within the latter, all being substantially as set forth. Y

PATRICK MIHAN. 

